Calculator



FIG. 1 is a front perspective view of a calculator;

FIG. 2 is a front view of the calculator of FIG. 1;

FIG. 3 is a top plan view of the calculator of FIG. 1;

FIG. 4 is a side elevation view of the calculator of FIG. 1; and,

FIG. 5 is a rear view of the calculator of FIG. 1. 

The ornamental design for a calculator, as shown and described. 